Software Development. This material exempt per Department of Commerce license exception TSU Xilinx, Inc. All Rights Reserved

Transcription

1 Software Development This material exempt per Department of Commerce license exception TSU 2007 Xilinx, Inc. All Rights Reserved

2 Objectives After completing this module, you will be able to: Identify the functionality included in the GNU tools: GCC, AS, LD, GDB Understand the basic concepts of the Eclipse IDE List Xilinx Software Development Kit (SDK) features Examine the IP driver s functionality and design Examine the Xilinx Libraries Determine what a BSP is and what is included

3 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries Board Support Packages Boot Files and Sequence

4 Desktop versus Embedded Desktop development: written, debugged, and run on the same machine OS loads the program into the memory when the program has been requested to run Address resolution takes place at the time of loading by a program called the loader The loader is included in the OS The programmer glues into one executable file called ELF Boot code, application code, RTOS, and ISRs Address resolution takes place during the gluing stage The executable file is downloaded into the target system through different methods Ethernet, serial, JTAG, BDM, ROM programmer

5 Embedded versus Desktop Development takes place on one machine (host) and is downloaded to the embedded system (target) Host Computer Off & On-Chip Memory Core Connect TM Target Computer Firmware #Include stdio.h Main() PPC405 Dbg Facilities CPU Trace Port CPU JTAG Port Control Post First Release Other PPC405 Cores SystemICE Core OCM IF CS ICON Cores I/O Selection On-Chip Memory User Ports GB I/O Port Std JTAG Port A cross-compiler is run on the host

6 Embedded Development Different set of problems Unique hardware for every design Reliability Real-time response requirement (sometimes) RTOS versus OS Code compactness High-level languages and assembly

7 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

8 Library Generation (LibGen) Library Generation MSS MHS Hardware Platform Generation CompEDKLib IP Models CompXLib ISE Models Testbench Stimulus IP Library or User Repository EDK SW Libraries LibGen Drivers, MDD MPD, PAO PlatGen SimGen.a PCore HDL System and Wrapper HDL system.bmm Behavioral VHD Model Embedded Software Development Synthesis (XST) NGC ISE Tools Application Source.c,.h,.s UCF NGDBuild SimGen Compiler (GCC).o Linker (GCC) NGD MAP NCD, PCF PAR Structural VHD Model NCD system.bit BitGen SimGen ELF BitInit download.bit system_bd.bmm Timing VHD Model Simulation Simulation Generator download.cmd impact

9 Software Design Environment The Library Generator (LibGen) utility generates the necessary libraries and drivers for the embedded system LibGen takes an MSS (Microprocessor Software Specification) file created by the user as input. The MSS file defines the drivers associated with peripherals, standard input/output devices, interrupt handler routines, and other related software features The MSS file is generated by XPS by using the software settings specified

10 LibGen Generated Directories project_directory Processor instance directory code directory include directory lib directory libsrc directory LibGen Configures libraries and device drivers Note: The number of processor instance directories generated is related to the number of processor instances present in the system code directory A repository for EDK executables Creates xmdstub.elf for MB here include directory C header files that are required by drivers xparameters.h Defines base and high addresses of the peripherals in the system Defines the peripheral IDs required by the drivers and user programs Defines the function prototypes

11 LibGen LibGen Generated Directories project_directory processor instance directory code directory include directory lib directory libsrc directory Note: The processor instance directories content is overwritten every time LibGen is run lib directory libc.a, libm.a and libxil.a libraries The libxil library contains driver functions that the particular processor can access libsrc directory Intermediate files and makefiles that compile the libraries and drivers Peripheral-specific driver files that are copied from the EDK and user driver directories

12 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

13 Software Platform Settings Software settings can be assigned to individual processor instance by selecting Software Software Platform Settings or clicking button on the toolbar In case of multiple processors in the design software platform settings allow you to select each processor instance and set parameters

14 Software Platform Settings (1) 1 2 Select Software Platform panel Select processor instance Select OS 4 Check desired libraries and their version 3 4

15 Software Platform Settings(2) 1 2 Select OS and Libraries panel Select processor instance Set stdin and stdout devices as well as assign fpu, malloc, and profiling related parameters Configure selected libraries parameters 4

16 Software Platform Settings(3) 1 Select Drivers panel 2 Select drivers and version for each device in the design 1 2

17 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

18 Compiler Settings Compiler settings can be assigned by double-clicking Compiler Options entry under an application in the Application tab Environment tab Application Mode Executable XmdStub (MicroBlaze processor only) Use Custom Linker Script If checked then provide the path to the linker script Use default Linker Script Program Start Address Stack Size Heap Size

19 Compiler Settings Debug and Optimization tab Optimization Parameters Optimization Level: 0 to 3 While debugging your code, level 0 (no optimization) is recommended Levels 1 and above will cause code rearrangement Use Global Pointer Optimization Compiler stores all variables up to 8 bytes of size in a special area that can be accessed by registers r2/r13 (called small data anchors) and a 16-bit offset Generate Debug Symbols Checking this option allows the generation of debugging information based on the option selected Create symbol for debugging (-g option) Create symbols for assembly (-gstabs option)

20 Compiler Settings Paths and Options tab Search Paths Library (-L) Include (-I) Libraries to Link against List user libraries to be used Other compiler options to append For example: -g See GNU docs for more options

21 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

22 Software Development with GNU Tools Library Generation MSS MHS Hardware Platform Generation CompEDKLib IP Models CompXLib ISE Models Testbench Stimulus IP Library or User Repository EDK SW Libraries LibGen Drivers, MDD MPD, PAO PlatGen SimGen.a PCore HDL System and Wrapper HDL system.bmm Behavioral VHD Model Embedded Software Development Synthesis (XST) NGC ISE Tools Application Source.c,.h,.s UCF NGDBuild SimGen Compiler (GCC).o Linker (GCC) NGD MAP NCD, PCF PAR Structural VHD Model NCD System.bit BitGen SimGen ELF Data2MEM download.bit system_bd.bmm Timing VHD Model Simulation Simulation Generator Download.cmd impact

23 GNU Tools: GCC GCC translates C source code into assembly language GCC also functions as the user interface to the GNU assembler and to the GNU linker, calling the assembler and the linker with the appropriate parameters Supported cross-compilers: GNU GCC (mb-gcc) Command line only; uses the settings set through the GUI C files Cross-compiler Assembly files

24 Calls four different executables Preprocessor (cpp0) Replaces all macros with definitions defined in the source and header files Language specific c-compiler cc1 C-programming language cc1plus C++ language Assembler mb-as Linker and loader mb-ld GNU Tools

25 GNU Tools: AS Input: Assembly language files File extension:.s Output: Object code File extension:.o Contains Assembled piece of code Constant data External references Debugging information Typically, the compiler automatically calls the assembler Use the -Wa switch if the source files are assembly only and use gcc Assembly files Cross-assembler Object files

26 GNU Tools: LD Linker Inputs: Several object files Archived object files (library) Linker script (mapfile) Output: Executable image (.ELF) Object files Linker/Locator Linker script Executable

27 GNU Utilities See Embedded System Tools Reference Manual for Complete List of utilities AR Archiver Create, modify, and extract from libraries Used in EDK to combine the object files of the Board Support Package (BSP) in a library Used in EDK to extract object files from different libraries Object Dump Display information from object files and executables Header information, memory map Data Disassemble code

28 MicroBlaze Object Dump Display summary information from the section headers mb-objdump h executable.elf Section Name Byte alignment Section Size Virtual Memory Address Loadable Memory Address Offset from the beginning of the section header table

29 MicroBlaze Object Dump Dumping the source and assembly code mb-objdump S executable.elf Memory location Machine Language Instruction Assembly instruction C code instruction

30 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

31 Software Development Environment: XPS 1 Lists Software Projects (Specifies processor instance, groups source code according to instance, xparameters.h, source and header files) Standard text editor for creating c/c++ applications 3 Console displays status, errors, and warnings 3

32 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

33 Software Development Environment: SDK Java-based application development environment Based on the open-source effort by the Eclipse Consortium\ Feature-rich C/C++ code editor and compilation environment Project management Application build configuration and automatic Makefile generation Error Navigation Well-integrated environment for seamless debugging of embedded targets Source code version control

34 Eclipse/CDT Frameworks Builder framework Compiles and Links Source files Default Build options are specified when application is created: Choice of Debug, Release, Profile configurations User can custom build options later when developing application Build types: Standard Make, Managed Make Launch framework Specifies what action needs to be taken: Run (+ Profile) application or Debug application In SDK, this is akin to the Target Connection settings Debug framework Launches debugger (gdb), loads application and begins debug session Debug views show information about state of debug session Hides ugliness of debug details Search framework Helps development of application Help System Online help system; context-sensitive

35 SDK Application Development Flow Platform Studio Generate Hardware Platform Generate Software Platform libraries, drivers Create software App Project Add sources + Edit Platform Studio SDK Compile + Link Debug / Profile Import ELF file, Download to board Yes Done? Libraries can be generate/updated from SDK

36 Workspaces and Perspectives Workspace Location to store preferences & internal info about Projects Transparent to SDK users In SDK, source files not stored under Workspace Views, Editors Basic User interface element Perspectives Collection of functionally related views Layout of views in a perspective can be customized according to user preference

37 Views Eclipse Platform views: Navigator view, Tasks view, Problems view Debug views: Stack view, Variables view C/C++ views: Projects view, Outline view

38 C/C++ Perspective 1 2 C/C++ project outline displays the elements of a project with file decorators (icons) for easy identification C/C++ editor for integrated software creation Code outline displays elements of the software file under development with file decorators (icons) for easy identification 4 Problems, Console, Properties view lists output information associated with the software development flow 4

39 Opening Perspectives and Views To open a Perspective, use Window Open Perspective To open a view, use Window Show View If the view is already present in the current perspective, the view is highlighted

40 bracket matching syntax coloring content assist refactoring keyboard shortcuts Editors

41 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

42 Device Drivers The Xilinx device drivers are designed to meet the following objectives: Provide maximum portability The device drivers are provided as ANSI C source code Support FPGA configurability Supports multiple instances of the device without code duplication for each instance, while at the same time managing unique characteristics on a perinstance basis Support simple and complex use cases A layered device driver architecture provides both Simple device drivers with minimal memory footprints Full-featured device drivers with larger memory footprints Ease of use and maintenance Xilinx uses coding standards and provides well-documented source code for developers

43 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

44 Drivers: Level 0 / Level 1 The layered architecture provides seamless integration with (Layer 2) RTOS application layer (Layer 1) High-level device drivers that are full-featured and portable across operating systems and processors (Layer 0) Low-level drivers for simple use cases Layer 2, RTOS Adaptation Layer 1, High-level Drivers Layer 0, Low-level Drivers

45 Drivers: Level 0 Consists of low-level device drivers Implemented as macros and functions that are designed to allow a developer to create a small system Characteristics: Small memory footprint Little to no error checking is performed Supports primary device features only No support of device configuration parameters Supports multiple instances of a device with base address input to the API Polled I/O only Blocking function calls Header files have _l in their names (for example, xuartlite_l.h)

46 Drivers: Level 1 Consists of high-level device drivers Implemented as macros and functions and designed to allow a developer to utilize all of the features of a device Characteristics: Abstract API that isolates the API from hardware device changes Supports device configuration parameters Supports multiple instances of a device Polled and interrupt driven I/O Non-blocking function calls to aid complex applications May have a large memory footprint Typically, provides buffer interfaces for data transfers as opposed to byte interfaces Header files do not have _l in their names (for example, xuartlite.h)

47 Comparison Example Uartlite Level 1 XStatus XUartLite_Initialize (XUartLite *InstancePtr, Xuint16 DeviceId) void XUartLite_ResetFifos (XUartLite *InstancePtr) unsigned int XUartLite_Send (XUartLite *InstancePtr, Xuint8 *DataBufferPtr, unsigned int NumBytes) unsigned int XUartLite_Recv (XUartLite *InstancePtr, Xuint8 *DataBufferPtr, unsigned int NumBytes) Xboolean XUartLite_IsSending (XUartLite *InstancePtr) void XUartLite_GetStats (XUartLite *InstancePtr, XUartLite_Stats *StatsPtr) void XUartLite_ClearStats (XUartLite *InstancePtr) XStatus XUartLite_SelfTest (XUartLite *InstancePtr) void XUartLite_EnableInterrupt (XUartLite *InstancePtr) void XUartLite_DisableInterrupt (XUartLite *InstancePtr) void XUartLite_SetRecvHandler (XUartLite *InstancePtr, XUartLite_Handler FuncPtr, void *CallBackRef) void XUartLite_SetSendHandler (XUartLite *InstancePtr, XUartLite_Handler FuncPtr, void *CallBackRef) void XUartLite_InterruptHandler (XUartLite *InstancePtr) Uartlite Level 0 void XUartLite_SendByte (Xuint32 BaseAddress, Xuint8 Data) Xuint8 XUartLite_RecvByte (Xuint32 BaseAddress)

48 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environment XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

49 Interrupt Management With Interrupt Controller The interrupt controller is required if more than one interrupting device is present Connect peripheral s interrupt requesting signals to the Intr port of the interrupt controller in the MHS file e.g., PORT Intr = RS232_Interrupt & interrupt_push & interrupt_timer Connect interrupt controller output intc to a processor interrupt pin e.g., PORT Irq = interrupt_req Define an external requesting signal, if needed, in the global ports section of the MHS file e.g., PORT interrupt_in1 = interrupt_in1, DIR = IN, LEVEL = low, SIGIS = Interrupt Connect the external interrupt signal to the Intr port of the interrupt controller

50 Interrupt Management Without Interrupt Controller The interrupt controller is not required when only one interrupting device is present The interrupt signal of the peripheral (or the external interrupt signal) must be connected to the interrupt input of the MicroBlaze processor in the MHS file Software interface for the interrupt Define the signal in MSS file to associate them to peripherals e.g., PARAMETER int_handler = uart_int_handler, int_port = Interrupt Write an interrupt handler routine to service the request The base address of the peripheral instance can be accessed as XPAR_INSTANCE_NAME_BASEADDR

51 MicroBlaze Interrupts One INTERRUPT port on the MicroBlaze processor MicroBlaze processor functions void microblaze_enable_interrupts(void) This function enables interrupts on the MicroBlaze processor When the MicroBlaze processor starts up, interrupts are disabled. Interrupts must be explicitly turned on by using this function void microblaze_disable_interrupts(void) This function disables interrupts on the MicroBlaze processor. This function may be called when entering a critical section of code where a context switch is undesirable

52 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

53 Integration in EDK When the interrupt generating device is connected to the processor interrupt pin, either through an interrupt controller or directly, the interrupt handler function must be developed (You must explicitly write code to set up the interrupt mechanism) The interrupt handler must be registered explicitly in code Registering an Interrupt Handler

54 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

55 Libraries Xilinx provides three libraries Math library (libm) The math library is an improvement over the newlib math library The -lm option is used for libm functions Standard C language support (libc) The functions of this library are automatically available Xilinx C drivers and libraries (libxil) Xilinx file support functions: Fatfs Xilinx memory file system: Mfs Xilinx networking support: lwip Xilinx flash memory support: Flash

56 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

57 What is a BSP? Board Support Package (BSP): Lowest layer of software modules used to access processor specific functions Interrupt and Exception Handling Instruction and Data Cache Handling Fast Simplex Link interface macros Program Profiling Allows you to use IP peripheral-device drivers GPIO, IIC controller, PCI controller, UART Offers glue functionality to link code against standard libraries Time, sleep Files Memory Standalone BSP (no operating system) Libgen generates libxil.a library

58 Hardware IP Device Drivers Driver Provides an interface for the software to communicate with the hardware Designed to be portable across processor architectures and operating systems Delivery format Delivered as source code, allowing it to be built and optimized Minimized assembly language C programming language

59 Outline Introduction Software Settings Software Platform Settings Compiler Settings GNU Development Tools: GCC, AS, LD, Binutils Development Environments XPS SDK Device Drivers Level 0, Level 1 MicroBlaze Processor: Interrupts Integration in EDK Libraries BSP Boot Files and Sequence

60 Boot Files The compiler includes pre-compiled startup and end files in the final link command when forming an executable Startup Files setup the language and the platform environment before your application code executes The following actions are typically performed Setup any reset, interrupt, and exception vectors as required Setup stack pointer, small-data anchors, and other registers Clear the BSS memory regions to zero Invoke language initialization functions, such as c++ constructors Initialize the hardware subsystem (ie. initialize profiling timers if the program is to be profiled) Setup arguments for the main procedure and invoke it Invoke language cleanup functions, such as c++ destructors De-Initialize the hardware sub-system (ie. clean up the profiling subsystem if the program was profiled) See Embedded System Tools reference manual for details

61 First Stage Initialization Files crt0.s used for programs which are to be executed in standalone mode, without the use of any boot loader crt1.s used when the application is debugged in a software-intrusive manner crt2.s Used when the executable is loaded using a boot loader crt3.s Employed when the executable does not use any vectors and wishes to reduce code size

62 Second Stage Initialization Files crtinit Default second stage C startup file pgcrtinit Used during profiling sim-crtinit Used when the mno-clearbss switch is used in the compiler sim-pgcrtinit Used during profiling in conjunction with the mno-clearbss switch

63 crt0.s Application entry point at label _start _start Set up any reset, interrupt, and exception vectors as required Transfers control to crtinit (see next slide) On returning from _critinit, it ends the program by infinitely looping in the _exit label

64 crtinit Clear the BSS (.bss and.sbss sections) memory regions to zero Invokes _program_init: language initialization functions, such as C++ constructors Invokes constructor functions (_init): Initializes interrupt handler and the hardware sub-system Set up arguments for main() and invokes main() Invokes destructor functions (_fini) Invokes _program_clean and returns

65 Skills Check

66 Knowledge Check What GNU GCC option is used to specify that debugging information should be placed in the executable? What is included in a BSP? What are some of the differences between a Level 0 and a Level 1 driver?

67 Answers What GNU GCC option is used to specify that debugging information should be placed in the executable? -g What is included in a BSP? IP drivers Processor functions Library functions What are some of the differences between a Level 0 and a Level 1 driver? Size Functionality Ease of use

68 Knowledge Check List libraries supported and their functionality How many interrupt pins are present on MicroBlaze?

69 Answers List libraries supported and their functionality Fatfs provides file support functions MFS provides memory file system support functions lwip provides networking support functions including handling of multiple connections Flash provides read/write/erase types of functions for Intel parallel flash devices so user can program flash memory during run-time How many interrupt pins are present on MicroBlaze? One

70 Where Can I Learn More? Tool documentation Embedded System Tools Guide Microprocessor Software Specifications Embedded System Tools Guide Microprocessor Driver Definition Embedded System Tools Guide Microprocessor Library Definition EDK OS and Libraries Reference Guide LibXil File, Net, and Kernel Processor IP Reference Guide Xilinx Drivers Processor documentation MicroBlaze Processor Reference Guide Support website EDK Website: